Diamond wheel



FIG. 1 is a front elevational view of a diamond wheel showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is an elevational plan view thereof;

FIG. 4 is a left side elevational plan view thereof; and,

FIG. 5 is a cross-sectional view along the A—A line. 

The ornamental design for a diamond wheel, as shown and described. 